Injectable veterinary iron compositions



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Unitd Se@ Pat@ 2,982,690 INJECTABLE VETERINARY RON COMPOSITIONS.

Karl A. Ratcltf, Des Moines, Iowa, assigner, by in esne assignments, to Diamond Laboratories, Des Momes, Iowa, a limited partnership Filed May 26, 1958, Ser. No. 737,484

9 Claims. (Cl. 16T-68) the disadvantage of possible toxic effects, relatively strong alkalinity, iniiammation at the Vsite of injection `and lack of absorption.

Recently it has been proposed to replace such saccharated iron oxide by a non-.ionic ferrie hydroxide-dextran complex. Dextran, however, is also a carbohydrate, being a polymer of sucrose. Moreovenvin such process the dextran employed must be specially prepared by rst polymerizing sucrose with the aidof appropriate microorganisms and then the dextran must be carefully depolymerized to a relatively narrow range of intrinsic viscosity.

It is an object of the present invention to prepare a composition containing substantially non-ionic iron for the treatment of iron-deficiency anemia which eliminates the disadvantages of the saccharated iron oxide and ferric hydroxide-dext-ran complexes recited above.

An additional object is to prepare a water soluble ferrie hydroxide-enzyme digested protein complex which can be used to treat iron-deficiency anemia which is well tolerated and can be injected, e.g., either intramuscularly or intravenously, without undesirable side etfects.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modiiications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

It has now been found that these objects can be attained by enzyme digesting a ferrie hydroxide-protein Y complex and then dissolving the digested complex in an aqueous alkaline solution of a pentitol or hexitol toy form a water solubleV non-ionic ferrie hydroxide-enzyme digested protein complex. It is surprising that it is possible to dissolve the complex after digestion without destruction of the complex itself since normally it would be expected that digestion of the initial complex with enzyme would release the iron from the complex and return it to the ionic form.

A iiow diagram of the process according to this invention is shown in the drawing. The general procedure employed is asy follows.` A non-toxic water soluble ferric salt, e.g., ferrie chloride,` ferrie nitrate, ferrie sulfate, ferrie citrate, ferrie ammonium sulfate or ferrie acetate, in either hydrous or anhydrous form, is dissolved in deionized or distilled water. Y

Patented May 2, 1961 ICC gelatin, in water, e.g., by adding gelatin slowly to warm deionized or distilled water with constant mixing until completely dissolved or homogeneous.

The ferrie salt solution and protein solution are mixed thoroughly. There is then slowly added a dilute solution of an alkali such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate or potassium carbonate with rapid mixing until a gelatinous iron complex is formed. A test sample is taken and checked for free ferrie iron after a complete and thorough washing of the precipitated protein-iron complex, eg., gelatinferrie hydroxide complex.

When a negative free ferrie iron test is obtained', the precipitated compound formed is mixed intimately with an enzyme such as papain, icin, or pepsin. The mixture is then incubated for a time suflicient to liquefy or digest the protein complex. Generally, when the digestion is completed,ran iron determination will indicate a concentration of Fe per cc. after concentration, preferably at least 5S-60 lmgs. Fe per cc. The product is filtered, e.g., through `a Buechner funnel. To the filtered product, having a concentration of '55 to 60 mgs. of Fe per cc., is added-an alkalinized solution of a pentitol or hexitol hav'- inig aco'ncentration of 50 to 70%, preferably about 70%, of the pentitol or hexitol. The alkaline pentitol 'or hexitol is made by adding an alkali to the polyhydric alcohol in an amount sulcie'nt to give a pH of atleast l2. f l

As the alkali, there can be used sodium hydroxide, potassium hydroxide, sodium carbonatefor potassium. carbonate. Generally, 15 to 20 c'c. of 60% sodium-hydroxide solution are Vused per 100 cc. of a '70% Sorbitol soluveterinary use for therapeutic purposes.

tion.

Sorbitol is used 4as the polyhydric alcohol and this alkaline polyhydric alcohol is added to the protein-iron complex slowly with constant stirring until the iron is dissolved. This usually occurs when a pH of approximately 10.5 to l1 is reached.

The pH is then adjusted back to the desired value, eg., a pH of 7.0 to 7.5, preferably approximately neutral, such as a pH of 7.2 to 7.3, using a saturated solution of citric acid or other non-toxic organic acid, eg., gluconic acid.

The iron content of the solution is rechecked. Any additional ingredients which may be desired can be added at this point and then the solution diluted to the nal concentration, filtered, if necessary, and sterilized in conventional fashion, eg., using l0 lbs. per square inch steam pressure for 30 minutes, or by filtration through a suitable bacterial yilter.

In testing a preparation according to the present invention for intramuscular toxicity in mice, I have not been able to inject quantities large enough to kill because of the limitations of quantity in intramuscular injections. The protein-iron complex solutions of the'present invention are non-toxic, can be injected parenterally, e.g.,

subcutaneously or intramuscularly, and are'suitable for They have been employed successfully, for example, with mice, dogs, and cattle. f

Throughout the specification and claims unless otherwise indicated,y all parts andfpercentagesvare by weight.

y Example' 31,454.32 gms. of deionized water with constant mixing until solution was complete. 1500 grams of gelatin were slowly added to.6 gallonsuof warm (approximately 610? I C.) deionized water withv constant mixing until homo- There is'then formed a solution of a protein suchvas geneous. f l

The gelatin and ferrie chloride solutions were vthen o thoroughly admixed and immediately afterwards 3 gallons 483.3.67 grams of ferrie chloridev were dissolved of 50% sodium hydroxide solution were added slowly with rapid mixing until a gelatinous iron complex was formed. The precipitated gelatinized iron was thoroughly washed with water andY test ksamples were taken-and checked for ionic ferrie iron.

When a negative yfree ferrie iron test was obtained, th productwas intimately mixed with a 1% papain solution added at a ratio of 1 gm. papain to 2000 gms. of gelatinized iron complex. The mixture was incubated at 38 to 43 C. for at least 7 days to liquefy the gelatin complex. The mixture which had a concentration of about 55 mgs. Fe per cc. was filtered through a Buechner funnel.

To. the ltered solution was addedv alkalinized `70% sorbitol with constant stirring until a pH- of about 10.5

5. A processaccording to claim 4 wherein the enzyme is papain.

v' is papain.

8. The process of preparing Va water soluble substan-k 2. A composition according to claim 1 wherein the enzyme is selected from the group consistng'of papain, cn andpepsin.

' 3. A composition according to claim 1 wherein the enzyme is papain.

' 4. A veterinary process which comprises parenterally administering to an animal a therapeutic amount of a substantiallyk non-ionic complex of -ferric iron with an enzyme digested gelatin together with sorbitol.

6. The process of preparing a water soluble substantially non-ionic ferric iron enzyme digested gelatin complex which comprises digesting a ferrie iron gelatin complex with an enzyme and adding an alkaline solution of sorbitol to said enzyme digested complex.

7.A process according to claiml wherein the enzyme tially non-ionic ferrie iron enzyme digested protein complex which comprises combiningin water a water soluble ferric salt vand gelatin,L adding an alkali to precipitate a ferrie iron gelatin complex, mixing said complex with papain, allowing said papain toract on said complex for a time suliicient to digest the complex, adding a strongly alkaline solution of sorbitol to said digested complex to dissolve thesame.

9. A process according to rclaim 8 including the furtherA step of substantially Vneutralizing the alkaline sorbitol' containing digested complex.

References Cited in the le of this patent UNITED STATES PATENTS v '906,474y Turner etal. i'. Dee. s, 190s 2,215,233 Ruskin sept. 17, 1940 2,816,060 Carter Dec. 10, 1957 2,820,740 London et a1. Jan. 21, 1958 2,822,317 Gulesich etal Feb. 4, 1958 FOREIGN PATENTS l vCanada 2 Mar. 27, 1956 

1. A COMPOSITION COMPRISING A SUBSTANTIALLY NON-IONIC COMPLEX OF FERRIC IRON WITH AN ENZYME DIGESTED GELATIN AND SORBITOL. 